Why office air conditioning standards are not designed for women

If you assume your female colleagues are making a fuss when the air conditioning comes on, think again: office thermal standards were simply not built with women in mind. They were worked out more than 50 years ago, by men and for men, and they have never been properly updated.

As soon as summer returns-especially this week, which has been utterly dreadful-air conditioning is switched back on in many workplaces. Although employment law does not require employers to equip their premises with it, it is clearly more comfortable to work in a mild atmosphere with recirculated air. Even so, that comfort is far from universal: for a large proportion of women, the first day the AC comes back marks the start of a long season of coping with temperatures that are too cold-levels their male colleagues typically find perfectly bearable.

A feeling shared by many, and one a team of researchers in California and Australia set out to demonstrate with hard data. In a study published on 8 December 2021 in Scientific Reports, they show that workplace temperatures are not at all suited to women.

Even though the research was carried out in the United States, employees in France face the same situation: the thermal rules used in offices follow the same international standards built around PMV (Predicted Mean Vote), later embedded in ISO 7730, which applies across European countries. Now badly out of date, these standards contain a design bias the scientific community had already identified in the 2000s-without standard-setting bodies responding by updating them. The mismatch feels particularly anachronistic at a time when some companies proudly display their “inclusivity charters”, equality labels, CSR commitments and other progressive reforms.

Women in the office: victims of air-conditioning sexism?

What the researchers compared (surveys and tweets)

To reach this conclusion, the researchers combined two independent data sources. The first was almost 39,000 responses from a survey of occupants in 435 office buildings spread across 168 US cities. The second, more informal and unusual, was 16,791 tweets posted between 2010 and 2019 by employees complaining about being cold at work.

What the results say about thermal discomfort

The first headline finding was that 38% of respondents said they were unhappy with the temperature in their workspace-nearly double the 20% threshold allowed by current thermal-comfort standards. Among those who were dissatisfied, women accounted for almost two thirds. In other words, the likelihood of feeling thermally uncomfortable was 1.8 times higher for them than for their male colleagues.

PMV and ISO 7730: standards built around a male reference body

As noted earlier, these standards were developed in the 1960s using the PMV model. This mathematical index was formalised by the Danish engineer Povl Ole Fanger, who calculated it using a so-called reference human body that was not really “universal” at all: a sedentary man wearing a suit and tie. The heat produced by his body (58.15 W/m²) was treated as a human constant, even though women’s resting metabolic rate is 20 to 35% lower than this.

In practical terms, women naturally generate less heat, meaning they typically need a higher ambient temperature to maintain thermal balance. That physiological gap was never incorporated into the PMV model, despite the model still being used worldwide.

The authors also flagged a second influence, more cultural and social in nature: in offices, men generally wear more layers than women. However, they qualify this point, arguing that-based on the data available-summer clothing differences between men and women are not large enough on their own to account for the thermal-comfort gap measured in the study.

Air conditioning: a small change that costs a lot

Productivity and the price of overcooling

This difference matters for work output, because the researchers found a strong link between perceived temperature and performance. Across the entire cohort, 42% of women felt the temperature harmed their ability to work, compared with 27% of men.

The authors attribute this 15-point gap directly to the prevalence of overcooling, not to any particular sensitivity to cold among women. They also argue that the explanations often cited in the scientific literature (lower metabolism or lighter clothing) create a perverse effect: in their view, they “frame women as the source of the problem, rather than office thermal environments themselves”. They also insist the issue is far from unsolvable, because it would simply require “raising office temperatures in summer, in line with thermal comfort standards”. This is within the reach of any company, and would “be enough to correct the gender bias linked to thermostat setpoints [editor’s note: the target temperature programmed into the thermostat]”, while also enabling organisations to cut their electricity bill and reduce their contribution, to a lesser extent, to global warming.